Wasmtime GitHub notifications bot (Mar 31 2026 at 13:19): Wasmtime GitHub notifications bot (Mar 31 2026 at 13:19):alexcrichton opened PR #12907 from alexcrichton:fix-aarch64-extr to bytecodealliance:main:
This commit fixes a miscompile in the lowering of the
extrinstruction for the aarch64 backend where one of the shift operands is 0. In this edge case the generatedextrinstruction did not match the input CLIF semantics, calculating a different value. The fix here is to only use theextrinstruction when both immediates are larger than 0.<!--
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Wasmtime GitHub notifications bot (Mar 31 2026 at 13:19):alexcrichton requested wasmtime-compiler-reviewers for a review on PR #12907.
Wasmtime GitHub notifications bot (Mar 31 2026 at 13:19):alexcrichton requested fitzgen for a review on PR #12907.
Wasmtime GitHub notifications bot (Mar 31 2026 at 13:19):alexcrichton requested wasmtime-core-reviewers for a review on PR #12907.
Wasmtime GitHub notifications bot (Mar 31 2026 at 15:42):cfallin submitted PR review:
Good find!
Wasmtime GitHub notifications bot (Mar 31 2026 at 15:42):cfallin added PR #12907 aarch64: Fix miscompile lowering the extr instruction to the merge queue.
Wasmtime GitHub notifications bot (Mar 31 2026 at 16:24):cfallin merged PR #12907.
Wasmtime GitHub notifications bot (Mar 31 2026 at 16:24):cfallin removed PR #12907 aarch64: Fix miscompile lowering the extr instruction from the merge queue.
Last updated: Apr 12 2026 at 23:10 UTC